Hi. The 2 day "tourist special" tickets are just $20 more than the one day; I would go for that.Knowing you have 2 days gives you a chance to really experience the park, not only the rides. They also have a front of the line pass for $179-$254 (depending on day you go)...personally, I wouldn't pay that. Whatever you do, get there before opening to avoid some of the crowds. Harry Potter Land is the most popular right now. Have fun.
By the way...Dottie, what rv park did you find convenient to Universal? We usually just drive down to so cal and stay in a hotel, but would be nice to bring the rv.